Catheters for the introduction or removal of fluids may be located in various venous locations and cavities throughout the body for introduction or removal of these fluids. Such catheterization may be performed by using a single catheter having multiple lumens. A typical example of a multiple lumen catheter is a dual lumen catheter in which one lumen introduces fluid and the other lumen removes fluid.
Generally, to insert any catheter into a blood vessel, the vessel is identified by aspiration with a long hollow needle in accordance with the well known Seldinger technique. When blood enters a syringe attached to the needle, indicating that the vessel has been found, a thin guide wire is then introduced, typically through a syringe needle or other introducer device into the interior of the vessel. The introducer device is then removed, leaving the guide wire within the vessel. The guide wire projects beyond the surface of the skin. At this point, several options are available to a surgeon for catheter placement. The simplest is to pass a catheter into the vessel directly over the guide wire. The guide wire is then removed, leaving the catheter in position within the vessel. However, this technique is only possible in cases where the catheter is of a relatively small diameter, made of a stiff material, and not significantly larger than the guide wire, for example, for insertion of small diameter dual lumen catheters. If the catheter to be inserted is significantly larger than the guide wire, a dilator device is passed over the guide wire to enlarge the hole. The dilator is removed and the catheter is then passed over the guide wire. After the catheter is inserted, the guide wire is removed.
For chronic catheterization, in which the catheter is intended to remain inside the patient for an extended period of time, such as for weeks or even months, it is typically desired to subcutaneously tunnel the catheter using various tunneling techniques. The catheter is typically tunneled into the patient prior to inserting the catheter into the patient's vein. The catheter typically includes a catheter ingrowth cuff that allows skin tissue forming the subcutaneous tunnel, to grow into the ingrowth cuff to secure the catheter subcutaneously to the patient. The catheter also typically includes a hub that extends proximally of the subcutaneous tunnel. The hub usually includes at least one suture wing that allows the surgeon to suture the hub to the patient's skin, to further secure the catheter to the patient.
There may be times when it is more advantageous, such as depending on the patient or the implanting surgeon's skill, to perform the tunneling after the catheter is implanted in the patient. For some catheters, though, such as multiple lumen catheters with a hub and with bonded luers on the proximal ends of the catheters, it is impractical to perform the tunneling after the catheter is installed in the patient. It would be beneficial to provide a catheter assembly having a hub configuration that provides a surgeon with alternative installation procedures for installing the catheter that better suit either the patient's needs or the surgeon's skills. Further, while catheters are provided to surgeons in standard sizes, patients come in all different sizes and in all different conditions, and what may be a suitable place to suture a hub in one patient may be a poor place to suture a hub in another patient. It would therefore be beneficial to provide a hub that can be disposed along the catheter to a particular location as determined by the surgeon, based on the size and condition of each particular patient.
Further, since the catheter is intended to be in the patient for an extended period of time, the hub, which may be fairly large as compared to the diameter of the catheter, may cause inconvenience to the patient. It would therefore be beneficial to be able to remove the hub at some time after installation of the catheter so that the hub does not inconvenience the patient.